Dual thrust bearing chair swivel

ABSTRACT

The present invention relates to chair swivel mechanisms with an automatic return-to-center function when the occupant exits the chair or changes the loading on the chair. The chair swivel of the present invention improves upon existing chair swivels through use of dual thrust bearings to manage repeated and uneven loading of the swivel mechanism in high use environments.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/807,377, filed Apr. 2, 2013, the contents of which are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to swivel mechanisms used with chairs and stools, such as restaurant/bar stools and casino stools, which have an automatic return-to-center feature.

BACKGROUND OF THE INVENTION

A common drawback in currently available swivel mechanisms with an automatic return-to-center feature is the limited lifespan of the device. The lifespan of currently available swivel mechanisms is generally on the order of a few thousand swivel cycles, e.g. loading and swiveling of the chair. These devices fail as moving parts wear out and the frictional forces produced while the chair is loaded become greater than the return-to-center biasing force exerted by the spring member in the swivel mechanism. These circumstances are particularly present when the load on the chair is unbalanced, which is typical. These devices will only continue to operate as intended when the chair is free from loading. Accordingly, it is an object of the present invention to swivel smoothly in the presence of an unbalanced load on the chair to enhance and increase the useful lifespan of the swivel mechanism.

SUMMARY OF THE INVENTION

The chair swivel of the present invention comprises an anchor plate rotatably mated with a mounting plate at a spindle extending from the mounting plate; a first rotary bearing mounted to the spindle; a first biasing member configured to operatively engage the spindle and anchor plate, and a second rotary bearing mounted to the spindle. The mounting plate is transformable from a first, neutral position to a second, non-neutral position in response to a first load applied to the biasing member wherein the restorative force of the biasing member returns the mounting plate to the first, neutral position, and the mounting plate transformable from the first, neutral position to a third, non-neutral position in response to a second load applied to the biasing member wherein the restorative force of the biasing member returns the mounting plate to the first, neutral position. The first and second rotary bearings are thrust bearings. The mounting plate is rotatable about a first axis and the second, non-neutral position is rotated a first direction from the first, neutral position about the first axis and the third, non-neutral position is rotated a second direction from the first, neutral position about the first axis and the first direction is opposite the second direction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of the present invention;

FIG. 2 is a perspective view of a first embodiment of the chair swivel mechanism of the present invention;

FIG. 3 is a first exploded perspective view of the first embodiment of the chair swivel mechanism of the present invention;

FIG. 4 is a second exploded perspective view of the first embodiment of the chair swivel mechanism of the present invention;

FIG. 5 is a first exploded perspective view of a second embodiment of the chair swivel mechanism of the present invention;

FIG. 6 is a top plan view of the first embodiment of the chair swivel mechanism of the present invention;

FIG. 7 is a cross-section elevation view of the first embodiment of the chair swivel mechanism of the present invention taken along line 7-7 in FIG. 6;

FIG. 8 is a bottom plan view of the first embodiment of the chair swivel mechanism of the present invention;

FIG. 9 is a side perspective view of the first embodiment of the chair swivel mechanism of the present invention;

FIG. 10 is a side elevation view of the first embodiment of the chair swivel mechanism of the present invention; and

FIGS. 11 and 12 are side perspective views of the first embodiment of the chair swivel mechanism of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The appended FIGS. 1-12 show a gaming chair 10 and dual thrust bearing chair swivel 22 in accordance with the present invention. The gaming chair 10 is shown in FIG. 1 as it would appear when positioned before, for example, a gaming machine 12 on a casino floor 14. The gaming chair 10 comprises: a pedestal 16, a seat 18, optionally including a back 20, and a chair swivel 22, consisting of the dual thrust bearing swivel of the present invention, to rotatably mount the seat 18 to the upper end of the pedestal 16. The chair swivel 22 holds the seat 18 in a first, neutral position wherein it “faces” the gaming machine 12. A person desiring to occupy the gaming chair 10 will rotate seat 18 approximately 120 degrees from the first, neutral position to a second, non-neutral position, will occupy the seat 18 and then turn back towards the first, neutral position to face the gaming machine 12. This occurs automatically by way of the chair swivel 22 with or without the assistance of the occupant. Upon leaving the gaming chair 10 the occupant will again rotate the seat 18 approximately 120 degrees from the first, neutral position and when the occupant leaves seat 18, the chair swivel 22 will automatically return the seat 18 to the first, neutral position facing the gaming machine 12.

A chair swivel to be used in this type of application must be designed to accommodate a significant number of complex loading and unloading cycles. Even when the gaming chair 10 is not occupied, the chair swivel encounters loading from the weight and eccentric location of the chair components. In the gaming or casino setting, this loading may further include heavy electronics components 20 a (e.g. speakers, displays, etc.) that may be built into the back 10. As shown in FIG. 1, the weight of the chair components will generate a moment arm and loading of the chair swivel 22. Rotation of the seat 18 and adding/removing the weight of the occupant, which will also be eccentric, further stresses and complicates the loading experienced by the chair swivel 22.

Turning to FIGS. 2-12, the inventive chair swivel 22 generally comprises an anchor plate 24, a mounting plate 26, a first biasing member 28, a first and second rotary bearing 30, 32 and at least a first locking washer 34. A second locking washer 36 may also be utilized. A central axis 84 runs through the pedestal 16 and through the chair swivel 22. The anchor plate 24 is shown to be generally rectangular with bores 38 a-d around the periphery of the anchor plate 24 to provide means for securing the swivel 22 to the pedestal 16. The anchor plate 24 is shown to be generally rectangular with, in this embodiment, curved or bowed sides. It will be understood that any suitable shape for the anchor plate 24 and arrangement and number of mounting bores 38 can be utilized. The anchor plate 24 further comprises a central bore 40 and collar 42 fitted into the central bore 40. The collar 42 has an inner diameter that corresponds to an outer diameter of a spindle 44 extending from the mounting plate 26, enabling the collar 42 and central bore 40 to receive the spindle 44 and releasably and rotatably mate the anchor plate 24 and mounting plate 26. The anchor plate 24 includes a first and second extension 46, 48 (best seen in FIG. 4), extending away from the anchor plate 24 in a substantially perpendicular manner. The first and second extensions 46, 48 each include a notch 50, 52 for engaging an opposing end of the first biasing member 28. As shown in FIG. 4, the first notch 50 on the first extension 46 is adjacent the surface of the anchor plate 24 and the second notch 52 is spaced away from the surface of the anchor plate 24 to accommodate the different heights of opposing ends of the first biasing member 28.

The biasing member 28 is preferably a coil spring with a first and second arm 54, 56 extending outwardly from the biasing member 28. The first and second arms 54, 56 are at different “heights” due to the configuration of a coil spring. Each of the first and second arms 54, 56 comprises a proximal piece 54 a, 56 a and distal piece 54 b, 56 b, with each proximal and distal piece connected by a bend. The proximal pieces 54 a, 56 a extend away from the biasing member 28 and diverge from each other. The distal pieces 54 b, 56 b extend further away from the biasing member 28 parallel to each other. The proximal pieces 54 a, 56 a may each include a sleeve 58 for sound and vibration dampening during operation of the swivel 22. The inner diameter of the biasing member 28 is greater than the outer diameter of the collar 42 enabling the biasing member 28 to fit over the collar 42. While the biasing member 28 has been described as a coil spring, any suitable spring or, alternatively, another structural element capable of providing the desired biasing force can be utilized.

The mounting plate 26 is shown to be rectangular in shape but can be any suitable size and shape for providing proper anchoring and support of the seat 18. A series of bores 60 a-d are located at the outer corners of the mounting plate and are configured to receive a fastener such as a screw, rivet, or the like to secure the mounting plate 26 to the seat 18 (FIG. 1). A central spindle or axle 44 extends from the mounting plate 26 in a substantially perpendicular manner and the distal end of the spindle 44 is externally threaded 62. As shown best in FIG. 3, a first and second mounting plate extension 64, 66 extend away from the mounting plate parallel to the spindle 44. The first and second mounting plate extensions 64, 66 will align adjacent to the first and second anchor plate extensions 46, 48 when the spindle 44 is received by the central bore 40 and collar 42 of the anchor plate 24 and the anchor plate 24 and mounting plate 26 are rotatably and releasably mated together.

A first and second notch 68, 70 in the first and second mounting plate extensions 64, 66 correspond with the notches 50, 52 on the first and second anchor plate extensions 46, 48 and are also configured to engage the first and second biasing member arms 54, 56. In this configuration, the anchor plate first extension 46 and mounting plate first extension 64 form a first forward stop 72 (FIG. 10) and the anchor plate second extension 48 and mounting plate second extension 66 form a second forward stop 74 (FIG. 10). A rear stop 76 is located on the mounting plate 26 opposite the first and second forward stops 72, 74 and includes a first and second rear stop surface 78, 80. The first and second rear stop surfaces 78, 80 may optionally include elastomeric stop elements 82 a, 82 b for absorbing vibration and for noise reduction while the swivel mechanism 22 is in operation.

The spindle 44 is of a length sufficient to extend through the first rotary bearing 30, anchor plate 24, and second rotary bearing 32. The outer diameter of the spindle 44 corresponds to the inner diameter of the first and second rotary bearings 30, 32 enabling the spindle 44 to fit through the first and second rotary bearings 30, 32. The first rotary bearing 30 will slide onto the spindle 44 and come to rest adjacent the mounting plate 26 and the top surface of the collar 42. The second rotary bearing 32 will slide onto the spindle 44 and to rest adjacent the anchor plate 24. The outer diameter of the first rotary bearing 30 is less than the inner diameter of the first biasing member 28 enabling the first biasing member 28 to fit over the first biasing member 28. In one embodiment of the present invention, the first and second rotary bearings 30, 32 consist of a suitable thrust bearing. Other suitable bearings may be used in provided that they are designed to permit rotation between parts while supporting an axial load.

As shown in FIG. 5 and FIG. 7 the chair swivel 22 may further include a separator or spacer 90 inserted between the biasing member 28 and first rotary bearing 30 to preclude the biasing member 28 from contacting the first rotary bearing 30 during operation of the swivel 22 as the biasing member 28 compresses and its diameter decreases. A first and second locking washer 34, 36 are internally threaded to match the external threading 62 on the spindle 44. Engaging the locking washers 34, 36 and the external threading 62 on the spindle 38 secures the components of the chair swivel 22 together. The swivel 22 described herein can also operate with the anchor plate engaging the seat and mounting plate engaging the pedestal without sacrificing performance of the chair swivel 22.

When the anchor plate 24 and mounting plate 26 are properly mated together, the anchor plate 24 seats on the spindle 44 and the first and second anchor plate extensions 46, 48 and the first and second mounting plate extensions 64, 66 will align and address/engage the associated first or second biasing member arm 54, 56. Specifically, notches 50, 68 will address and engage the first arm 54 and notches 52, 70 will address and engage the second arm 56. When the mounting plate 26 is rotated in a clockwise direction the second anchor plate extension 48 and second anchor plate notch 52 will anchor the biasing member 28 at the second biasing member arm 56 and the first mounting plate extension 64 and first mounting plate notch 68 will load the biasing member 28 by biasing/urging the first biasing member arm 54 clockwise and away from the anchored second biasing member arm 56. Continued loading of the biasing member 28 is restricted by the second biasing member arm 56 coming into contact with the first rear stop surface 78, precluding further clockwise rotation of the first biasing member arm 54 and further opening of the biasing member 28.

When the mounting plate 26 is rotated in a counter-clockwise direction the first anchor plate extension 46 and first anchor plate notch 50 will anchor the biasing member 28 at the first biasing member arm 54 and the second mounting plate extension 66 and second mounting plate notch 70 will load the biasing member 28 by biasing/urging the first biasing member arm 54 counter-clockwise and away from the anchored second biasing member arm 56. Continued loading of the biasing member 28 is restricted by the first biasing member arm 54 coming into contact with the second rear stop surface 80, precluding further clockwise rotation of the first biasing member arm 54 and further opening of the spring 28.

In operation, the biasing 28 biases the gaming chair 10 into a first, neutral position wherein the gaming chair 10 “faces” the gaming machine 12 and the biasing member 28 is also in a first, relaxed or neutral position. The gaming chair 10 may be rotated clockwise about the central axis 84 extending through the pedestal 16 and chair swivel 22 into a second, non-neutral position away from the gaming machine 12 where the occupant can occupy or exit the seat 18. The biasing member 28 will be in a second, loaded or non-neutral position. Likewise, the gaming chair 10 may be rotated counter-clockwise about the central axis 84 into a third, loaded or non-neutral position away from the gaming machine 12 where the occupant can occupy or exit the seat 18. The biasing member 28 will be in a third, loaded or non-neutral position. Continued rotation of the gaming chair 10 is restricted by the biasing member arms 54, 56 coming into contact with the rear stop member 76. Rotation of the mounting plate 26 in either the clockwise or counter-clockwise direction will load the biasing member 28.

Frictional forces generated from the occupant sitting in the gaming chair 10 including the chair swivel 22 and placing his/her feet on the ground or holding onto a stationery object will maintain the gaming chair 10 in the second or third non-neutral position and will maintain the biasing member 28 in the loaded/compressed state. A full release of the load (from the occupant in the seat standing up) or shifting of the load (the occupant lifts his/her feet partially or fully from the ground) wherein the frictional forces are less than the restorative force of the biasing member will cause the biasing member 28 to recoil back to its first, neutral position and return the gaming chair 10 to its first, neutral position facing the gaming machine 12. In this configuration, the mounting plate 26 is able to rotate in both a clockwise and counter-clockwise direction about the axis 84 with a return-to-center function.

As is evident from the design of the present inventive chair swivel 22 and the disclosure made herein, the device is intended to accommodate complex loading situations where a static load generates a force vector that runs parallel to the central axis 84 of the pedestal 16 towards the floor 14 and dynamic loads comprising downward loading and rotational loading about the first axis 86 generated as the chair swivels from the first, neutral position to the second, non-neutral position or third, non-neutral position. The shortcomings of prior art swivel mechanisms arise from the inability for smooth operation when the mechanism is not loaded in a balanced manner. Any swiveling action that occurs in an unbalanced loading situation introduces excess wear and tear to the swivel mechanism and eventually the frictional forces exerted by the worn down components will be greater than the spring biasing force. This will lead to complete disfunctionality of swiveling function, e.g. the swivel mechanism becomes permanently locked in place or external assistance is required to urge the swivel mechanism back to its original position. Incorporation of the second thrust bearing in the present inventive dual thrust bearing chair swivel provides balanced loading of the mechanism, lengthening the useful service life of the mechanism to approximately 100,000 or more swivel cycles.

Utilization of the first and second rotary bearings 30, 32 enables the components of the chair swivel 22 to tightly secure together, thus preventing wobbling of the mounting plate 26, while still facilitating free rotation of the mounting plate 26 during operation. Tightly securing the components of the chair swivel 22 enables uneven and eccentric loading of the seat 18 to be better distributed, reducing wear on the chair swivel components during operation. This aspect is particularly significant when the chair swivel is used in high usage situations, such as on casino floors where players frequently move in and out of chairs and shift their weight while playing games.

While the present invention has been described in connection with a specific application, this application is exemplary in nature and is not intended to be limiting on the possible applications of this invention. It will be understood that modifications and variations may be effected without departing from the spirit and scope of the present invention. It will be appreciated that the present disclosure is intended as an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated and described. The dual thrust bearing chair swivel is admirably suited for use with casino gaming machines, the chair swivel is also well suited for use with counter stools, dinette chairs, and various other products. 

I claim:
 1. A chair swivel comprising: an anchor plate rotatably mated with a mounting plate including a spindle extending therefrom; a first rotary bearing mounted to the spindle; a first biasing member configured to operatively engage the spindle and anchor plate, the mounting plate transformable from a first, neutral position to a second, non-neutral position in response to a first load applied to the biasing member wherein a restorative force of the first biasing member returns the mounting plate to the first, neutral position, and the mounting plate transformable from the first, neutral position to a third, non-neutral position in response to a second load applied to the biasing member wherein the restorative force of the first biasing member returns the mounting plate to the first, neutral position; and a second rotary bearing mounted to the spindle.
 2. The chair swivel of claim 1 wherein the first and second rotary bearings are thrust bearings.
 3. The chair swivel of claim 1 wherein the mounting plate is rotatable about a first axis and the second, non-neutral position is rotated a first direction from the first, neutral position about the first axis and the third, non-neutral position is rotated a second direction from the first, neutral position about the first axis and the first direction is opposite the second direction.
 4. The chair swivel of claim 3 wherein the first direction is counter-clockwise and the second direction is clockwise.
 5. The chair swivel of claim 1 wherein the biasing member is a coil spring.
 6. The chair swivel of claim 1 wherein the first rotary bearing mounts on the spindle below the mounting plate and the second rotary bearing is mounted on the spindle below the anchor plate.
 7. The chair swivel of claim 1 wherein the first rotary bearing mounts on the spindle and the biasing member mounts on the spindle over the first rotary member.
 8. A swiveling chair comprising: a pedestal having a length; a chair swivel mounted to the pedestal, the chair swivel comprising: an anchor plate rotatably mated with a mounting plate including a spindle extending therefrom, a first rotary bearing mounted to the spindle, a first biasing member configured to operatively engage the spindle and anchor plate, the mounting plate transformable from a first, neutral position to a second, non-neutral position in response to a first load applied to the biasing member wherein a restorative force of the first biasing member returns the mounting plate to the first, neutral position, and the mounting plate transformable from the first, neutral position to a third, non-neutral position in response to a second load applied to the biasing member wherein the restorative force of the first biasing member returns the mounting plate to the first, neutral position, and a second rotary bearing mounted to the spindle; and a seat attached to the chair swivel.
 9. The swiveling chair of claim 8 wherein the first and second rotary bearings are thrust bearings.
 10. The swiveling chair of claim 8 wherein the mounting plate is rotatable about a first axis extending through the length of the pedestal and the second, non-neutral position is rotated a first direction from the first, neutral position about the first axis and the third, non-neutral position is rotated a second direction from the first, neutral position about the first axis and the first direction is opposite the second direction.
 11. The swiveling chair of claim 10 wherein the first direction is counter-clockwise and the second direction is clockwise.
 12. The swiveling chair of claim 8 wherein the biasing member is a coil spring.
 13. The swiveling chair of claim 8 wherein the first rotary bearing mounts on the spindle below the mounting plate and the second rotary bearing is mounted on the spindle above the mounting plate.
 14. The chair swivel of claim 8 wherein the first rotary bearing mounts on the spindle and the biasing member mounts on the spindle over the first rotary member. 